A. Field of the Invention
The present invention relates to a new and improved device for advancing workpieces to a work station that is adjacent to a coining head in a high speed press.
B. Description of the Prior Art
High speed presses are often employed to coin metal workpieces. To attain the high press speeds desirable, the workpieces must be rapidly advanced to a work station whereupon the coining operation is performed. Prior art presses employ a dial to advance the workpieces. The dial is rotated in incremental steps and includes apertures on its periphery for holding a workpiece such that upon incremental rotation of the dial, workpieces are sequentially positioned at the work station of the press.
Several different prior art devices are employed to rotate the dial. One prior art device is an electrical mechanism separate from the press that rotates the dial in a programmed sequence.
Another prior art device is a pneumatic mechanism controlled by a separate pneumatic assembly that is programmed for a predetermined advancement cycle.
These prior art devices present several disadvantages. One is that each of these prior art devices requires the employment of energy or actuating fluid separate from that employed in the press. Consequently, completely different mechanisms separate from the press are necessary increasing the complexity and cost of the press.
Another disadvantage of a separate unit controlling the incremental advancement of the dial is that the separate mechanism must be programmed to advance the dial in a predetermined fashion. If the press stops or malfunctions, the advancing mechanism may continue to operate as programmed resulting in damage to the press. In addition, if the press is operating in the normal fashion but the advancing mechanism malfunctions, damage may occur.
A further disadvantage of the prior art advancing mechanisms is that the speed at which they may cycle is limited by the mechanical restraints of the mechanism and the structure connecting it to the press thus preventing operation at the high speeds desired.